The NEI Central Transgenic Animal Production Facility is a research support facility for all NEI intramural researchers requiring the use of transgenic mice in their research programs. We are currently providing transgenic animal support to researchers from three laboratories in the NEI (Laboratory of Immunology, Laboratory of Molecular and Developmental Biology, and laboratory of Retinal Cell and Molecular Biology); in our program, 125 DNA constructs are currently at various stages of completion. NEI researchers using molecular biology techniques to study the eye submit DNA constructs to our section for production of transgenic mice. We create transgenic mice by standard procedures, then biopsy and perform DNA analysis on the mice that are born from these procedures to identify positive mice. At researchers' request, we mate positive transgenic mice, wean litters, biopsy and analyze DNA from successive generations of transgenic mice, provide the transgenic animals to researchers, and cryopreserve and bank embryos from important mouse lines (both transgenic and naturally occurring). Over the year, we have generated 147 transgenic founder mice from 37 DNA constructs; set up 337 matings of transgenic mice; weaned, tagged, and tail biopsied 2,828 mice; isolated DNA from 3,507 samples; and performed 3,848 DNA analyses. This year, 2,842 embryos have been frozen to preserve seven mouse lines, bringing NEI's inventory to 3,448 cryopreserved embryos from 14 mouse lines. In addition to service functions, we also collaborate with NEI researchers on transgenic animal projects. We are currently collaborating with NEI researchers to develop a transgenic rat mode.